Magnetic separators are today used in a variety of applications that call for ferrous and non-ferrous materials to be separated. One such application is that wherein a device known as a magnetic trap is incorporated into a conduit to collect metallic debris that may happen to pass through the conduit. In some cases the presence of such ferrous materials is expected as where the trap is used in an engine oil circulation system. In other cases, such as with air ducts, the appearance of metallic objects in an air stream is unexpected but must be guarded against as a protective measure.
Proper incorporation of magnetic traps into conduits is not an easy task. For example, where an existing pipeline or duct system has to have a section of its wall removed to receive a magnetic trap, substantial care must be exercised to ensure that once incorporated the line or duct is completely resealed to avoid leaks. This particularly true where the fluid stream passing through the conduit contains fluids in their liquid state. In addition, a magnetic trap must often be incorporated into a pipeline or duct system in such a manner that it may be removed or accessed periodically for maintenance. It frequently occurs that traps are not actually cleaned until such time that the build-up of debris therein has reached a point restricting stream passage. This problem is commonly avoided through periodic inspections of the traps. However, this constitutes an inefficient trial and error technique that results in traps often being inspected more frequently than the need arising for cleaning.
Accordingly, it is seen that a need remains for a magnetic trap that may be easily and effectively incorporated into conduits and the like. A need also remains for a magnetic trap that is self monitoring with regard to the condition of the trap so that the existence of an actual need for maintenance may be easily recognized. Therefore, it is to the provision of such a magnetic trap that the present invention is primarily directed.